n the second season, much of the crew is changed. Gone are the older cast members except for Roy Scheider, with the introduction of mostly young characters. These include Dr. Smith (Rosalind Allen), who replaces Stephanie Beacham as the ship's doctor. She's also a psychic, which plays into several storylines. Then there's Tony Piccollo (Michael DeLuise), who is sort of a wise-guy and has been augmented with gills, like a fish, and can breath underwater. Also among the new crew is helmswoman Lonnie Henderson (Kathy Eveson), who is on board just for the "cute" factor, though she unlikely ends up becoming like Ripley from Alien by the last episode of the season. The most entertaining and interesting new character is Dagwood (Peter DeLuise) a GELF (Genetically Enhanced Life Form). The Gelf's were created to be the ultimate soldiers and are stronger and need less oxygen to breath than normal humans. Dagwood was one of the first to be created, though he's anything but a soldier, being far more like Lenny from OF MICE AND MEN. However, the show still has Lucas Wolenczak and Darwin, the talking dolphin.

The episodes are much more fantastical than in the first season, presenting an earth that needs huge air refineries to produce oxygen since the rain forests were destroyed. In the first two episodes a renegade colony of Gelf's start destroying them, as they can survive with less air.

There's some chemistry between Nathan Bridger and Dr. Smith, though they get that straightened out. Commander Jonathan Ford (Don Franklin), who was so uptight in the first season, is more laid back, primarily because he's hanging out with Wolenczak, Piccolo and Dagwood.

The season ends with the Seaquest and crew being transported to another planet where they help stop an alien war. It ends with Wolenczak, Dagwood and Darwin as seemingly the only survivors, floating in an inflatable raft on an alien planet.